CNC Turning advice

[Leadhead]

Wish to cut some simple pipe bending rollers with a half round edge grooves 1/8, 3/16, 1/4 etc.
Programming is simple, but :-
Tooling :-
First option is to use >1/8" RNMG insert but of course too small to be practical.
2nd - Make an HSS form tool with side relief. Possibly on a parting blade. Difficult to get the rad. accurate?
3rd - Use a 35 deg 04mm rad tool and approach from two sides with R&L/H tool.

Any advice on good way to CNC these grooves very much appreciated.

[pippin88]

If I understand the task, I'd use a 35 degree insert in a straight holder. SVVCN holder.

[Leadhead]

But this would make an interference of 17.5 deg. at each side as the control point tries to interpolate the radius.

[m_c]

If I understand what you're trying to achieve, I'd probably go for a MDT (Multi-Directional Tool).

APT do ones that use WDN inserts - https://www.shop-apt.co.uk/external-grooving-tools-for-wdn-inserts-apt.html


You can't hog metal like you can with dedicated tools, but they're ideal for profiles that would otherwise need a change of tool, but material removal/being as fast as possible are not the top priorities.

Edit - APT also do MGMN style - https://www.shop-apt.co.uk/external-grooving-tools-for-mgmn-inserts.html which would also work. In fact most grooving tools can be used for light profiling/turning provided the insert is clamped in place.

[pippin88]

Much easier to help if you show us a picture of what you want to do.

[Leadhead]

Pippin - Simply an accurate semi circular cut in the side of 40mm dia. bar.